PCB Technical - Heavy Copper PCB

Printed circuit boards (PCBS) are usually bonded to a glass epoxy substrate with a layer of copper foil, usually of 18, 35, 55, and 70 microns thickness.The most commonly used copper foil is 35 microns thick.The thickness of copper foil used in China is generally 35 ~ 50 microns, but some are thinner than this, such as 10 microns, 18 microns;And thicker ones like 70 microns.The thickness of the composite copper foil on the substrate with l ~ 3mm thickness is about 35 microns.The thickness of composite copper foil on substrates less than 1MM thick is about 18 microns, and the thickness of compound copper foil on substrates more than 5mm thick is about 55 microns.If the PCB thickness of copper foil is 35 microns, printed wide 1mm, each 10 mm long, its resistance is about 5mΩ, its inductance for 4nH or so.When the di/dt of the digital integrated circuit chip on the PCB is 6mA/ns and the working current is 30mA, the resistance and inductance values contained in the printed line with a length of 10mm are used to estimate the noise voltage generated by each part of the circuit is 0.15mv and 24mV respectively.

iPCB.com can do 5oz(0.175mm) copper thickness.